4,000 Meters Below Sea Level, Scientists Have Found the Spectacular 'Dark Oxygen'
Nestled between Hawaii and the western coast of Mexico lies the Pacific Ocean’s Clarion-Clipperton Zone (CCZ), a 4.5 million-kilometer-square area of abyssal plain bordered by the Clarion and Clipperton Fracture Zones. Although this stretch of sea is a vibrant ecosystem filled with marine life, the CCZ is known best for its immense collection of potato-sized rocks known as polymetallic nodules. These rocks, of which there are potentially trillions, are filled with rich deposits of nickel, manganese, copper, zinc, cobalt. Those particular metals are vital for the batteries needed to power a green energy future, leading some mining companies to refer to nodules as a “battery in a rock.”
However, a new study reports that these nodules might be much more than simply a collection of valuable materials for electric cars—they also produce oxygen 4,000 meters below the surface where sunlight can't reach. This unexpected source of “dark oxygen,” as it’s called, redefines the role these nodules play in the CZZ. The rocks could also rewrite the script on not only how life began on this planet, but also its potential to take hold on other worlds within our Solar System, such as Enceladus or Europa. The results of this study were published in the journal Nature Geoscience.
“For aerobic life to begin on the planet,” Andrew Sweetman, deep-sea ecologist with the Scottish Association for Marine Science and lead author of the study said in a press statement, “there had to be oxygen and our understanding has been that Earth’s oxygen supply began with photosynthetic organisms. But we now know that there is oxygen produced in the deep sea, where there is no light. I think we therefore need to revisit questions like: where could aerobic life have begun?”
